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Pick a random value from an enum?
...ould suggest is caching the result of values() because each call copies an array. Also, don't create a Random every time. Keep one. Other than that what you're doing is fine. So:
public enum Letter {
A,
B,
C,
//...
private static final List<Letter> VALUES =
Collections.unmodifi...
Only get hash value using md5sum (without filename)
...
A simple array assignment works... Note that the first element of a bash array can be addressed by just the name without the [0] index, ie, $md5 contains only the 32 chars of the md5sum.
md5=($(md5sum file))
echo $md5
# 53c8fdfcbb...
Python: Select subset from list based on index set
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I see 2 options.
Using numpy:
property_a = numpy.array([545., 656., 5.4, 33.])
property_b = numpy.array([ 1.2, 1.3, 2.3, 0.3])
good_objects = [True, False, False, True]
good_indices = [0, 3]
property_asel = property_a[good_objects]
property_bsel = property_b[good_indices]
...
ASP.Net MVC: How to display a byte array image from model
I've a model with a byte array image file that I want to show on the page.
10 Answers
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Getting an object from an NSSet
...embership, use anyObject to get a member (not random), or convert it to an array (in no particular order) with allObjects.
A set is appropriate when you don't want duplicates, don't care about order, and want fast membership testing.
...
Convert bytes to a string
... Maybe this will help somebody further: Sometimes you use byte array for e.x. TCP communication. If you want to convert byte array to string cutting off trailing '\x00' characters the following answer is not enough. Use b'example\x00\x00'.decode('utf-8').strip('\x00') then.
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How to use cURL to get jSON data and decode the data?
... dump a beauty json :3
var_dump(json_decode($result, true));
Accessing
$array["threads"][13/* thread id */]["title"/* thread key */]
And
$array["threads"][13/* thread id */]["content"/* thread key */]["content"][23/* post id */]["message" /* content key */];
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How can I quantify difference between two images?
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General idea
Option 1: Load both images as arrays (scipy.misc.imread) and calculate an element-wise (pixel-by-pixel) difference. Calculate the norm of the difference.
Option 2: Load both images. Calculate some feature vector for each of them (like a histogram). Calcu...
Count the number of occurrences of a character in a string in Javascript
...thus the || []
The original answer I made in 2009 is below. It creates an array unnecessarily, but using a split is faster (as of September 2014). I'm ambivalent, if I really needed the speed there would be no question that I would use a split, but I would prefer to use match.
Old answer (from 200...
Convert from enum ordinal to enum type
...portTypeEnum value = ReportTypeEnum.values()[ordinal];
Please notice the array bounds.
Note that every call to values() returns a newly cloned array which might impact performance in a negative way. You may want to cache the array if it's going to be called often.
Code examp...